by Nate Ryan, USA TODAY Sports

by Nate Ryan, USA TODAY Sports

For the second consecutive Sprint Cup season, Tony Stewart's future is unclear after missing the August race at Watkins Glen International.

But unlike last season, when the three-time champion was certain to miss several races with a broken right leg, forecasting Stewart's comeback could be much trickier.

Beyond the mental anguish that caused him to sit out Sunday's Cheez-It 355 at The Glen after his sprint car struck and killed Kevin Ward Jr. in a Saturday night race at Canandaigua (N.Y.) Motorsports Park, Stewart also must deal with potential legal ramifications of the crash, which is being investigated by the Ontario County Sheriff's Department.

Sheriff Philip Povero said the investigation is being reviewed by the district attorney, and there had been no evidence to support intent or criminal charges. Eyewitness testimony and video still is being gathered as the sheriff's department seeks to reconstruct the crash. Autopsy results from the Monroe County Medical Examiner's Office still are pending for Ward, a native of Port Leyden, N.Y., and funeral arrangements also haven't been announced by the family, which released a statement Sunday requesting time to grieve.

Citing his emotional state, Stewart elected not to race Sunday at Watkins Glen, where he was replaced in the No. 14 Chevrolet by Regan Smith (who finished 37th).

NASCAR's premier series heads this weekend to Michigan International Speedway with four races remaining before the Chase for the Sprint Cup begins.

Stewart isn't qualified for the 10-race playoff, but he will retain his eligibility for making the Chase via a victory if he attempts to qualify Friday at Michigan. With A.J. Allmendigner's stunning victory Sunday at the Glen, 12 of the 16 spots in the Chase have been filled by race winners.

Because he is ranked 22nd in the points, Stewart's only shot at making the Chase for the first time in two years is via a victory â?? if he can return behind the wheel.